JP2012150469A - Coating compositions for use with over-coated photoresist - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide organic coating compositions to reduce reflection of exposing radiation from a substrate back into an over-coated photoresist layer and/or to function as a planarizing, conformal, or via-fill layer.SOLUTION: Antireflective coating compositions comprise a component that comprises one or more parabanic acid moieties.

Description

  The present invention relates to a paravanic acid composition that is particularly useful as a component of a coating composition that underlies an overcoated photoresist.

  Photoresist is a photosensitive film used to transfer an image to a substrate. A coating layer of photoresist is formed on the substrate, and then the photoresist layer is exposed to an activating radiation source through a photomask. The photomask has areas that are opaque to activating radiation and other areas that are transparent to activating radiation. Exposure to activating radiation results in light-induced or chemical conversion of the photoresist coating, thereby transferring the photomask pattern to the photoresist-coated substrate. After exposure, the photoresist is developed to provide a relief image that allows selective processing of the substrate.

  The primary use of photoresists is in semiconductor manufacturing aimed at converting highly polished semiconductor sections, such as silicon or gallium arsenide, into a complex matrix of electronic conduction paths that function as circuits. Appropriate photoresist processing is key to achieving this goal. Although there are strong interdependencies between the various photoresist processing steps, exposure is considered one of the most important steps to achieve a high resolution photoresist image.

  Reflection of the activating radiation used to expose the photoresist often limits the resolution of the image patterned in the photoresist layer. Reflection of radiation from the substrate / photoresist interface can cause spatial variations in radiation intensity within the photoresist, which can result in non-uniform photoresist linewidth in development. Radiation can scatter from the substrate / photoresist interface to areas of the photoresist that are not intended for exposure, which can also lead to linewidth variations.

  One attempt used to reduce the problem of reflected radiation has been the use of a radiation absorbing layer inserted between the substrate surface and the photoresist coating layer. See U.S. Patent Application Publication Nos. 20070426458 and 20110029556.

US Patent Application Publication No. 200706458 US Patent Application Publication No. 20110029556

  Electronic device manufacturers continue to seek increased resolution of photoresist images patterned on antireflective coating layers.

In one form, a resin comprising one or more parabanic acid moieties is provided.
Preferred resins of the coating composition of the present invention can contain one or more polyester chains. Preferred resins may contain groups such as uracil groups and / or cyanurate groups in addition to the paravanic acid moiety.
In a further aspect, a base coating composition is provided, including a base antireflective composition, comprising a component comprising one or more paravanic acid moieties. Preferred undercoating compositions of the present invention include those comprising a resin containing one or more paravanic acid moieties. Preferred additional components of the base coating composition include crosslinkable functional groups or materials. Preferred undercoating compositions are formulated as organic solvent compositions for spin-on application to desired substrates such as microelectronic wafers.

  Preferred undercoating compositions of the present invention are cross-linked prior to treatment to adjust the water contact angle. This cross-linking includes curing and a covalent bond forming reaction between one or more composition components.

  For antireflective applications, the undercoating composition of the present invention is also used to expose an overcoated resist layer and also includes a component that includes a chromophore that can absorb unwanted radiation that reflects back to the resist layer. Including. Such chromophores can be present in other composition components such as resins or acid generator compounds, or the composition can be optionally substituted phenyl groups, optionally substituted anthracene groups or optionally. Another component that can include a chromophore unit that includes one or more chromophore moieties, such as one or more of substituted naphthyl groups, eg, a small molecule (eg, less than about 1000 or less than 500 MW). Can be included. For the undercoating compositions of the present invention imaged at 193 nm with an overcoated photoresist, the paravanic acid portion of the paravanic acid component can function as an effective exposure radiation absorbing chromophore.

  The generally preferred chromophores included in the coating compositions of the present invention, particularly those used in antireflective applications, include both monocyclic and multi-ring aromatic groups such as optionally substituted phenyl, optionally substituted. Naphthyl, optionally substituted anthracenyl, optionally substituted phenanthracenyl, optionally substituted quinolinyl and the like. Particularly preferred chromophores can vary depending on the radiation used to expose the overcoated resist layer. More specifically, for overcoating resist exposure at 248 nm, optionally substituted anthracene and optionally substituted naphthyl are preferred chromophores of the antireflective composition. For overcoating resist exposure at 193 nm, optionally substituted phenyl and optionally substituted naphthyl are particularly preferred chromophores for antireflective compositions. Preferably, such chromophore is bound to the resin component of the antireflective composition (eg, a pendant group).

  As noted above, the coating composition of the present invention is preferably a crosslinkable composition, including, for example, a material that crosslinks or otherwise cures upon thermal or activating radiation treatment. Typically, the composition can include a crosslinker component, such as an amine-containing material, such as a melamine, glycouril or benzoguanamine compound or resin. Preferably, the crosslinkable composition of the present invention can be cured by heat treatment of the composition coating layer. Suitably the coating composition also comprises an acid or more preferably an acid generator compound, in particular a thermal acid generator compound, to promote the crosslinking reaction.

  For use as an antireflective coating composition, as well as for other uses, such as via fill, preferably the composition is crosslinked prior to applying a photoresist composition layer over the composition layer.

  A variety of photoresists can be used in combination (ie, overcoated) with the coating composition of the present invention. Preferred photoresists for use with the antireflective compositions of the present invention are chemically amplified resists, particularly one or more photoacid generator compounds and deblocking or cleavage in the presence of light generated acid. A positive photoresist comprising a unit that undergoes a reaction, for example a photoacid-labile-resin component comprising an ester, acetal, ketal or ether unit. Negative photoresists can also be used with the coating compositions of the present invention, such as resists that crosslink (ie, cure or solidify) upon exposure to activating radiation. Preferred photoresists for use with the coating compositions of the present invention are relatively short wavelength radiation, such as less than 300 nm, or less than 260 nm, such as radiation having a wavelength of about 248 nm, or less than about 200 nm, such as 193 nm. Can be imaged with radiation having a wavelength of. EUV and other high energy imaging is also suitable.

  The present invention further provides a method for forming a photoresist relief image and a novel article of manufacture comprising a substrate (eg, a microelectronic wafer substrate) coated with the coating composition of the present invention alone or in combination with a photoresist composition. provide.

Other forms of the invention are disclosed below.
The inventor provides a novel organic coating composition that is particularly useful for use with an overcoated photoresist layer. Preferred coating compositions of the present invention can be applied by spin coating (spin-on composition) and can be formulated as a solvent composition. The coating compositions of the present invention are particularly useful as antireflective compositions for overcoated photoresists and / or as planarizing or viafill compositions for overcoated photoresist composition coating layers.

  Preferred undercoating compositions of the present invention can exhibit fast reactive etch rates, as well as high refractive index (> 1.8), and low absorption at 193 nm that may be required for advanced lithographic applications. . Furthermore, preferred paravanic acid polymers of the present invention can exhibit high thermal stability.

  The parabanic acid component of the present invention includes parabanic acid (PBA) containing polymers, copolymers, terpolymers, tetrapolymers, and other higher order PBA containing polymers, and blends of these polymers.

  The parabanic acid component useful in the underlying organic coating composition of the present invention can be readily produced. For example, parabanic acid diacetate compounds are useful reagents and are generally prepared and used as described in the following examples.

Undercoat composition resin:
As noted above, preferred resins include resins that include one or more parabanic acid moieties. Suitably, the one or more paravanic acid moieties can be pendant to the resin backbone, or can be, for example, a resin backbone chain linked at each ring nitrogen of the paravanic acid group.

  The paravanic acid resin of the present invention can be synthesized by various methods, for example, polymerization of one or more monomers containing a paravanic acid group, for example, acidic or basic condensation reaction. Particularly preferred paravanic acid resin synthesis is shown in the examples below. Preferably, at least about 1, 2, 3, 4 or 5 percent of all repeating units of the formed resin, more preferably at least about 10, 15, 20, 25, 30, 35 of all repeating units of the formed resin. 40, 45, 50 or 55 percent contain one or more parabanic acid moieties.

  Particularly preferred parabanic acid resins of the present invention contain a polyester chain, i.e., in certain forms of the present invention, polyester resins are preferred. The polyester resin can be easily produced by the reaction of one or more polyol reagents and one or more parabanic acid-containing reagents. Suitable polyol reagents include diols, glycerol and triols such as diols, which include, for example, ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, butanediol, pentanediol, cyclohexane. Butyldiol, cyclopentyldiol, cyclohexyldiol, dimethylolcyclohexane, and triol are, for example, glycerol, trimethylolethane, trimethylolpropane, and the like. Particularly preferred polyol reagents are shown in the examples below.

  The resin of the coating composition of the present invention can contain various additional groups, for example, cyanurate groups as disclosed in US Pat. No. 6,852,421. An additional preferred resin unit is a uracil group as disclosed in US Provisional Application No. 61/428896.

  Particularly preferred resins of the present invention can contain one or more parabanic acid groups, one or more polyester linkages and optionally one or more cyanurate groups.

As discussed, for antireflection applications, one or more of the compounds that react to form a resin suitably absorbs radiation used to expose the overcoated photoresist coating layer. Contains a moiety that can function as a chromophore. For example, phthalate compounds (eg, phthalic acid or dialkyl phthalates (ie, diesters where each ester has 1 to 6 carbon atoms, preferably dimethyl phthalate or diethyl phthalate)) are aromatic or non-aromatic Polyesters that can be polymerized with polyols and optionally other reactive compounds, can be provided that are particularly useful in antireflective compositions for use with photoresists imaged at sub-200 nm wavelengths, eg, 193 nm. Similarly, resins used in compositions in combination with topcoat photoresists imaged at sub-300 nm wavelengths or sub-200 nm wavelengths such as 248 nm or 193 nm include naphthyl compounds such as 1 or 2 or more Naphthyl compounds with more carboxyl substituents can be polymerised, for example dialkyl naphthalenedicarboxylates, in particular di-C _1-6 alkyl. Also preferred are reactive anthracene compounds, such as anthracene compounds having one or more carboxy or ester groups, such as one or more methyl ester or ethyl ester groups.

  Compounds containing chromophore units can also contain one or preferably two or more hydroxy groups and can be reacted with carboxyl-containing compounds. For example, phenyl compounds or anthracene compounds having one, two or more hydroxyl groups can be reacted with a carboxyl-containing compound.

  In addition, the undercoating composition used for antireflection purposes can include substances containing chromophore units (eg, photoacid labile groups and / or bases) separately from the resin component that provides water contact angle adjustment. Resin containing reactive groups). For example, the coating composition can include polymeric or non-polymeric compounds that include units such as phenyl, anthracene, naphthyl, and the like. However, in many cases, one or more resins that provide water contact angle control and chromophore moieties are preferred.

  The resins of the undercoating composition of the present invention (including paravanic acid-containing resins) are preferably from about 1,000 to about 10,000,000 daltons, more typically from about 2,000 to about 100,000. It has a weight average molecular weight (Mw) of daltons and a number average molecular weight (Mn) of about 500 to about 1,000,000 daltons. The molecular weight (Mw or Mn) of the polymer of the present invention is appropriately determined by gel permeation chromatography.

  The parabanic acid-containing component (eg, parabanic acid-containing resin) is the majority solid component of the base coating composition in many preferred embodiments. As referred to herein, the solid content of the coating composition refers to all materials of the coating composition except the solvent carrier. In some forms, the paravanic acid-containing component can be a minor portion of the coating composition (eg, less than 50% of the total solids) and is suitably blended with one or more other resins that do not include paravanic acid substitution. Can be done.

  As indicated, preferred undercoating compositions of the present invention can be crosslinked, for example, by thermal and / or radiation treatment. For example, preferred undercoating compositions of the present invention can include a separate crosslinker component that can crosslink with one or more other components of the coating composition. In general, preferred crosslinkable coating compositions comprise a separate crosslinker component. Particularly preferred coating compositions of the present invention comprise a resin, a crosslinker and an acid source such as a thermal acid generator compound as separate components. Thermally induced crosslinking of the coating composition by activation of a thermal acid generator is generally preferred.

  Thermal acid generator compounds suitable for use in coating compositions include ionic or substantially neutral thermal acid generators to catalyze or promote crosslinking during curing of the antireflective composition coating layer. Examples thereof include ammonium arene sulfonate salts. Typically, one or more thermal acid generators are present in the coating composition in an amount of about 0.1 to 10 percent by weight of the total dry components of the composition (all components except the solvent carrier), more preferably total dry Present at a concentration of about 2 weight percent of the ingredients.

  Preferred crosslinkable coating compositions of the present invention also include a crosslinker component. A variety of cross-linking agents may be used, including the cross-linking agents disclosed in Shipley EP-A-542008 (incorporated herein by reference). For example, suitable coating composition crosslinkers include amine-based crosslinkers, such as melamine materials, such as those manufactured by Cytec Industries, Cymel 300, 301, 303, 350, 370, 380. And melamine resins sold under the trade names 1116 and 1130. Particularly preferred are glycolurils including glycoluril available from Cytec Industries. Benzoguanamine and urea based materials, including benzoguanamine resins available under the names Cymel 1123 and 1125 from Cytec Industries, and urea resins available under the names Powderlink 1174 and 1196 from Cytech Industries May also be suitable. In addition to those available commercially, such amine-based resins can be used, for example, by reaction of acrylamide or methacrylamide copolymers with formaldehyde in alcohol-containing solutions, or with N-alkoxymethylacrylamide or methacrylamide and other suitable. It can be produced by copolymerization with monomers.

  The crosslinker component of the coating composition of the present invention is generally in an amount of about 5 to 50 weight percent of the total solids of the antireflective composition (all components other than the solvent carrier), more typically the total solids. Present in an amount of about 7 to 25 weight percent.

  The coating composition of the present invention, particularly for reflection control applications, can also include additional dye compounds that absorb the radiation used to expose the overcoated photoresist layer. Other optional additives include surface leveling agents, for example, leveling agents available under the trade name Silwet 7604, or surfactants FC171 or FC431 available from 3M Company. Can be mentioned.

  The undercoating composition of the present invention can also include other materials such as photoacid generators, including photoacid generators as discussed for use with overcoated photoresist compositions. For a discussion of such use of photoacid generators in antireflective compositions, see US Pat. No. 6,261,743.

  In order to produce the liquid coating composition of the present invention, the components of the coating composition may comprise a suitable solvent, such as one or more oxyisobutyric acid esters, particularly methyl-2-hydroxyisobutyrate, lactic acid as described above. Ethyl, or one or more glycol ethers such as 2-methoxyethyl ether (diglyme), ethylene glycol monomethyl ether, and propylene glycol monomethyl ether; solvents having both ether and hydroxy moieties such as methoxybutanol, ethoxybutanol, methoxy Propanol and ethoxypropanol; methyl 2-hydroxyisobutyrate; esters such as methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate , Dipropylene glycol monomethyl ether acetate and other solvents such as dibasic esters, propylene carbonate and gamma - is dissolved like butyrolactone. The concentration of the dry ingredients in the solvent can depend on several factors such as the method of application. Generally, the solids content of the base coating composition varies from about 0.5 to 20 weight percent of the total weight of the coating composition, and preferably the solids content varies from about 0.5 to 10 weights of the coating composition.

Exemplary Photoresist Systems Various photoresist compositions such as positive and negative photoacid generating compositions can be used with the coating compositions of the present invention. The photoresist used with the antireflective composition of the present invention typically comprises a resin binder and a photoactive component, typically a photoacid generator compound. Preferably, the photoresist resin binder has functional groups that impart aqueous alkaline developability to the imaged resist composition.

  As mentioned above, a particularly preferred photoresist for use with the undercoating composition of the present invention is a chemically amplified resist, particularly a positive chemically amplified resist composition, which is photoactivated in this resist layer. The acid induces a deprotective reaction of one or more composition components, thereby resulting in a solubility difference between the exposed and unexposed areas of the resist coating layer. Many chemically amplified resist compositions are described, for example, in U.S. Pat. Nos. 4,968,581; 4,883,740; 4,810,613; 4,491,628 and 5,492. 793, No. 793. The coating composition of the present invention is particularly suitably used with a positive chemically amplified photoresist having an acetal group that undergoes deblocking in the presence of a photoacid. Such acetal-based resists are described, for example, in US Pat. Nos. 5,929,176 and 6,090,526.

  The undercoating composition of the present invention can also be used with other positive resists, for example, resists containing a resin binder containing polar functional groups such as hydroxyl or carboxylate, the resin binder being an alkaline aqueous solution thereof. It is used in the resist composition in an amount sufficient to make the resist developable. In general, preferred resist resin binders are phenolic resins, such as phenol aldehyde condensates, alkenyl phenol homo- and copolymers, and N-hydroxyphenyl-maleimide homo- and copolymers known in the art as novolak resins. Can be mentioned.

A preferred positive photoresist for use with the undercoating composition of the present invention comprises an imaging effective amount of a photoacid generator compound and one or more resins selected from the following group:
1) A phenolic resin containing an acid labile group that can provide a chemically amplified positive resist particularly suitable for image formation at 248 nm. Particularly preferred resins of this type include: i) polymers containing polymerized units of vinylphenol and alkyl acrylate, wherein the polymerized alkyl acrylate units are deblocked in the presence of a photoacid. A polymer that can be affected. Representative alkyl acrylates that can undergo photoacid-induced deblocking reactions include, for example, t-butyl acrylate, t-butyl methacrylate, methyl adamantyl acrylate, methyl adamantyl methacrylate, and photoacid-induced reactions. Other acyclic alkyl and alicyclic acrylates are included, such as the polymers in US Pat. Nos. 6,042,997 and 5,492,793; ii) include hydroxy or carboxy ring substituents Polymers containing polymerized units of alkyl acrylates such as the optionally substituted vinylphenyl (eg styrene), vinylphenol, and deblocking groups described for polymer i) above, such as US Pat. Polymers described in No. 042,997; and ii) a polymer comprising a repeating unit containing an acetal or ketal moiety capable of reacting with a photoacid, and optionally an aromatic repeating unit such as a phenyl or phenolic group; such a polymer is described in US Pat. No. 5,929,176. And 6,090,526:
2) A resin that can provide a chemically amplified positive resist that is substantially or completely free of phenyl or other aromatic groups and that is particularly suitable for imaging at sub-200 nm wavelengths, eg, 193 nm. Particularly preferred resins of this type include the following: i) polymers containing polymerized units of non-aromatic cyclic olefins (intracyclic double bonds), eg optionally substituted norbornene, eg US patents Polymers described in 5,843,624 and 6,048,664; ii) alkyl acrylate units such as t-butyl acrylate, t-butyl methacrylate, methyl adamantyl acrylate, methyl methacrylate Polymers comprising adamantyl and other acyclic alkyl and alicyclic acrylates; such polymers are disclosed in US Pat. Nos. 6,057,083; European Patent Publication Nos. EP01008913A1 and EP00930542A1; / 143,462; and iii) Polymers comprising combined acid anhydride units, in particular polymerized maleic anhydride and / or itaconic anhydride units, for example the polymers disclosed in European Patent Application Publication No. EP01008913A1 and US Pat. No. 6,048,662 :
3) contain repeating units containing heteroatoms, in particular oxygen and / or sulfur (but excluding acid anhydrides, ie the units do not contain keto ring atoms) and desirably substantially or completely aromatic Resin without unit. Preferably, the heteroalicyclic unit is fused to the resin backbone, more preferably the resin is a fused carbon alicyclic unit as provided by polymerization of norbornene groups, and / or maleic anhydride or It contains acid anhydride units as provided by the polymerization of itaconic anhydride. Such resins are disclosed in International Application No. PCT / US01 / 14914 and US Patent Application No. 09 / 567,634:
4) Resins that contain fluorine substitution (fluoropolymers), for example, resins that can be provided by polymerization of tetrafluoroethylene, fluorinated aromatic groups, such as fluoro-styrene compounds. Examples of such resins are disclosed, for example, in International Application No. PCT / US99 / 21912.

式中、Ｒはカンフル、アダマンタン、アルキル（例えば、Ｃ_１−１２アルキル）およびフルオロアルキル、例えば、フルオロ（Ｃ_１−１８アルキル）、例えば、ＲＣＦ_２−［式中、Ｒは場合によって置換されたアダマンチルである］である。 Suitable photoacid generators for use in positive or negative photoresists overcoated on the coating composition of the present invention include imide sulfonates such as compounds of the formula:

Wherein R is camphor, adamantane, alkyl (eg, C _1-12 alkyl) and fluoroalkyl, eg, fluoro (C _1-18 alkyl), eg, RCF _2- [where R is optionally substituted. It is adamantyl.

  Preference is also given to triphenylsulfonium PAG complexed with anions such as the above sulfonate anions, in particular perfluoroalkyl sulfonates, for example perfluorobutane sulfonate.

  Other known PAGs can also be used in the resists of the present invention. Particularly for 193 nm imaging, PAGs that do not contain aromatic groups, such as the imide sulfonates described above, are generally preferred in order to provide improved transparency.

  Other photoacid generators suitable for use in the compositions of the present invention include, for example, onium salts such as triphenylsulfonium trifluoromethanesulfonate, (p-tert-butoxyphenyl) diphenylsulfonium trifluoromethanesulfonate. , Tris (p-tert-butoxyphenyl) sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate; nitrobenzyl derivatives such as 2-nitrobenzyl p-toluenesulfonate, 2,6-dinitrobenzyl p-toluene Sulfonates and 2,4-dinitrobenzyl p-toluenesulfonate; sulfonate esters such as 1,2,3-tris (methanesulfonyloxy) benzene, 1,2,3-tris (trifluoromethane Sulfonyloxy) benzene, and 1,2,3-tris (p-toluenesulfonyloxy) benzene; diazomethane derivatives such as bis (benzenesulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane; glyoxime derivatives such as bis-O -(P-toluenesulfonyl) -α-dimethylglyoxime, and bis-O- (n-butanesulfonyl) -α-dimethylglyoxime; sulfonic acid ester derivatives of N-hydroxyimide compounds, such as N-hydroxysuccinimide methane Sulfonic acid esters, N-hydroxysuccinimide trifluoromethanesulfonic acid esters; and halogen-containing triazine compounds such as 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5 Triazine, and 2- (4-methoxynaphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine. One or more of such PAGs can be used.

  Preferred optional additives for the resists of the present invention are additional bases, particularly tetrabutylammonium hydroxide (TBAH) or tetrabutylammonium lactate, which can improve the resolution of the developed resist relief image. For resists imaged at 193 nm, the preferred additional base is tetrabutylammonium hydroxide lactate, as well as various other amines such as triisopropanol, diazabicycloundecene or diazabicyclononene. The additional base is suitably used in relatively small amounts, for example about 0.03 to 5 percent by weight relative to the total solids.

  A negative resist composition suitable for use with the topcoat composition of the present invention comprises a mixture of materials that cure, crosslink or solidify upon exposure to an acid and photoacid generator.

  Particularly preferred negative resist compositions comprise a resin binder such as the phenolic resin of the present invention, a crosslinker component and a photoactive component. Such compositions and their use are disclosed in European Patent Application Publication Nos. 0164248 and 0232972, and US Pat. No. 5,128,232 to Thuckeray et al. Preferred phenolic resins for use as the resin binder component include novolaks and poly (vinylphenol) s as described above. Preferred crosslinkers include amine based materials such as melamine, glycoluril, benzoguanamine based materials and urea based materials. Melamine formaldehyde resins are generally most preferred. Such crosslinkers are commercially available, for example, melamine resins are sold by Cytec Industries under the trade names Cymel 300, 301 and 303. Glycoluril resins are sold by Cytec Industries under the trade names Cymel 1170, 1171, 1172, and Powder Link 1174, and benzoguanamine resins are sold under the trade names Cymel 1123 and 1125.

  The photoresist of the present invention can also include other optional materials. For example, other optional additives include anti-striation agents, plasticizers, rate enhancers, dissolution inhibitors, and the like. Such optional additives typically include, except for fillers and dyes, which can be present in relatively high concentrations, for example, in an amount of about 5 to 30 weight percent of the total weight of the dry components of the resist. Can be present at low concentrations in the photoresist composition.

Lithographic Processing In use, the coating composition of the present invention is applied to a substrate as a coating layer by any of a variety of methods such as spin coating. The coating composition is generally applied onto the substrate with a dry layer thickness of about 0.02-0.5 μm, preferably with a dry layer thickness of about 0.04-0.20 μm. The substrate is preferably any substrate used in methods related to photoresist. For example, the substrate can be silicon, silicon dioxide, or an aluminum-aluminum oxide microelectronic wafer. Gallium arsenide, silicon carbide, ceramic, quartz or copper substrates can also be used. Substrates for liquid crystal display or other flat panel display applications such as glass substrates, indium tin oxide coated substrates, etc. are also preferably used. Substrates for optical and optoelectronic devices (eg, waveguides) can also be used.

  Preferably, the applied coating layer is cured before the photoresist composition is applied over the underlying coating composition. Curing conditions can vary depending on the components of the underlying coating composition. In particular, the curing temperature may depend on the specific acid or (thermal) acid generator used in the coating composition. Typical curing conditions are about 80 ° C. to 225 ° C. for about 0.5 to 5 minutes. Curing conditions preferably render the coating composition coating layer substantially insoluble in the photoresist solvent and the aqueous alkaline developer solution.

  After such curing, a photoresist is applied on the surface of the applied coating composition. For the application of the bottom coating composition layer, the overcoated photoresist can be applied by any standard means such as spinning, dipping, meniscus or roller coating. After application, the photoresist coating layer is typically dried by heating, and preferably the solvent is removed until the resist layer is no longer tacky. Optimally, intermixing of the bottom composition layer and the overcoated photoresist layer should essentially not occur.

The resist layer is then imaged with activating radiation through a mask in a conventional manner. The exposure energy is sufficient to effectively activate the photoactive component of the resist system to produce a patterned image in the resist coating layer. Typically, the exposure energy ranges from about 3 to 300 mJ / cm ^2, in part, depend on the particular resist and resist processing is exposure tool and use. The exposed resist layer can be subjected to a post-exposure bake if it is desired to create or increase the solubility difference between the exposed and unexposed areas of the coating layer. For example, negative curable photoresists typically require post-exposure heating to induce an acid-promoted crosslinking reaction, and many chemically amplified positive resists are exposed to induce an acid-promoted deprotection reaction. Requires post-heating. Typical post-exposure bake conditions include temperatures of about 50 ° C. or higher, more specifically temperatures in the range of about 50 ° C. to about 160 ° C.

  The photoresist layer is an immersion lithography system, i.e., the space between the exposure tool (especially the projection lens) and the substrate coated with the photoresist provides an immersion fluid, for example water or an increased refractive index fluid. It may be exposed in an immersion lithography system occupied with water mixed with one or more additives such as possible cesium sulfate. Preferably, the immersion liquid (eg, water) has been treated to avoid bubbles, eg, the water can be degassed to avoid nanobubbles.

  Reference herein to “immersion exposure” or other similar term refers to such a fluid layer (for example, where the exposure is inserted between the exposure tool and the applied photoresist composition layer (eg, Water or water containing additives).

  The exposed resist coating layer is then developed, preferably an aqueous developer such as tetrabutylammonium hydroxide, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, sodium silicate, metasilicic acid. Developed with alkali as exemplified by sodium, aqueous ammonia and the like. Alternatively, an organic developer can be used. In general, development follows recognized procedures. After development, a final bake of the acid curable photoresist is often performed at a temperature of about 100 ° C. to about 150 ° C. for several minutes to further cure the developed exposed coating layer area.

  For the developed substrate, those areas of the substrate where the photoresist has been removed can then be selectively processed, e.g., the substrate area where the photoresist has been removed is chemically treated according to procedures well known in the art. Can be etched or plated. Suitable etchants include hydrofluoric acid etching solutions and plasma gas etching, such as oxygen plasma etching. Plasma gas etching removes the underlying coating layer.

The plasma etch was performed by the following protocol: a coated substrate (eg, a substrate coated with an undercoating composition and a resist according to the present invention) had a pressure of 25 mT, a top power of 600 watts, 33CHF ₃ (Sccm), 7O ₂ (Sccm) and 80Ar (Sccm) are placed in the plasma etching chamber.

  The following non-limiting examples are illustrative of the invention. All documents mentioned herein are hereby incorporated by reference.

Example 1: Synthesis of parabanic acid resin Part 1:
Parabanic acid (20 g, 0.175 mol) was dissolved in tetrahydrofuran at a total solids concentration of 7%. Once a homogeneous solution was obtained, bromo t-butyl acetate (102.5 g, 0.525 mol) was added to the reaction flask, followed by DBU (79.8 g, 0.525 mol) slowly. The contents were cooled at room temperature. After reaching the equilibrium temperature, the contents were refluxed at 67 ° C. The contents were stirred overnight at this temperature. The next morning, a heavy precipitate of DBU-bromide slats was filtered off and the clear solution thus obtained was diluted with ethyl acetate. The organic phase was washed with 0.1N HCl solution to remove unreacted DBU. The organic phase was further washed with DI water and the organic was dried over sodium sulfate. The ethyl acetate fraction was dried under vacuum to give 40 g of the desired product. Monomer III thus obtained was analyzed by ¹³ C NMR. The resulting product was> 99% pure.

Part 2: A 100 ml three-necked round bottom flask equipped with an overhead stirrer, Dean Stark apparatus and thermocouple was added to diacetate parabanate (PBA) (10 g, 0.029 mol), tris (hydroxyethyl) prepared in Part 1 above. Isocyanurate (THEIC) (7.6 g, 0.029 mol), p-TSA (0.17 g), butanol (10 g) and anisole (13 g) were added. The contents were stirred and a reaction temperature of 150 ° C. was achieved. A total of 11 g of distillate was collected and the reaction was quenched by cooling to room temperature. The polymer thus formed was dissolved in NMP to give a 20% solution. The polymer was precipitated with iso-propanol / methyl t-butyl ether (50/50) to give a white powder (I). The resulting polymer was dried in a vacuum oven overnight to obtain 10 g polymer sample. The polymer was analyzed for molecular weight, composition, optical properties, TGA and DSC analysis and etch rate. This data is shown in Table 1. ^The composition determined by ¹³ C NMR was 6/41/53 (Bu-PBA / PBA / THEIC).

Example 2: Additional Paravanic Acid Resin Synthesis A 100 ml three-necked round bottom flask equipped with an overhead stirrer, Dean Stark apparatus and thermocouple was added to the parabanic acid diacetate (PBA) (10 g, prepared in Part 1 of Example 1 above). 0.029 mol), tris (hydroxyethyl) isocyanurate (THEIC) (7.6 g, 0.029 mol), p-TSA (0.17 g) and anisole (13 g) were added. The contents were stirred and a reaction temperature of 150 ° C. was achieved. A total of 11 g of distillate was collected and the reaction was quenched by cooling to room temperature. The polymer thus formed was dissolved in NMP to give a 20% solution. The polymer was precipitated with iso-propanol / methyl t-butyl ether (50/50) to give a white powder (II). The resulting polymer was dried in a vacuum oven overnight, yielding 9.5 g of polymer sample. The polymer was analyzed for molecular weight, composition, optical properties, TGA and DSC analysis and etch rate. This data is shown in Table 1. ^The composition determined by ¹³ C NMR is 49/51 (PBA / THEIC).

Example 3 Additional Paravanic Acid Resin Synthesis A 100 ml three-necked round bottom flask equipped with an overhead stirrer, Dean Stark apparatus and thermocouple was added to the parabanic acid diacetate (PBA) (14. 26 g, 0.042 mol), tris (hydroxymethyl) ethane (THME) (7.5 g, 0.063 mol), p-TSA (0.21 g) and anisole (15 g) were added. The contents were stirred and a reaction temperature of 150 ° C. was achieved. A total of 15 g of distillate was collected and the reaction was quenched by cooling to room temperature. The polymer thus formed was dissolved in THF to give a 20% solution. The polymer was precipitated with iso-propanol / methyl t-butyl ether (50/50) to give a white powder (III). The resulting polymer was dried in a vacuum oven overnight to obtain 12 g polymer sample. The polymer was analyzed for molecular weight, composition, optical properties, TGA and DSC analysis and etch rate. This data is shown in Table 1. ^The composition determined by ¹³ C NMR is 48/52 (PBA / THME).

上記ポリオールがポリマー（ポリエステルを含む）合成のために有用である。 Example 4: Di- and tri-functional alcohols

The above polyols are useful for polymer (including polyester) synthesis.

Example 5 Antireflective Composition Preparation 3.237 g of the polymer from Example 3, 5.768 g tetramethoxymethyl glycoluril, 0.371 g ammoniated para-toluenesulfonic acid, and 490.624 g methyl An antireflective casting solution containing 2-hydroxyisobutyrate is mixed and filtered through a 0.2μ Teflon filter.

Example 6 Lithographic Processing This formulated parabanic acid resin coating composition is spin coated onto a silicon microchip wafer and cured on a vacuum hotplate at 210 ° C. for 60 seconds to provide a cured coating layer. .

  A commercially available 193 nm positive photoresist is then spin coated onto the cured coating composition layer. The applied resist layer was soft baked on a vacuum hotplate at 100 ° C. for 60 seconds, exposed to patterned 193 nm radiation through a photomask, post-exposure baked at 110 ° C. for 60 seconds, and then 0.26 N aqueous alkaline Developed with a developer, both the photoresist layer and the underlying coating composition are removed in the areas defined by the photomask.

Example 7: Polymer analysis Strip data was performed by coating three separate organic coating compositions: each of these compositions contained: 1) Examples 1, 2 and 3 respectively. 2) a thermal acid generator (1%), and 3) a glycouril-based crosslinking agent (10-15%). The coating was found to be 200-500 mm. Crosslinking was effected effectively by baking the membrane at 150 ° C to 250 ° C. The cross-linked material was soaked in the desired solvent for 60 seconds and then shaken off the membrane. The film thickness loss is shown in Table 1 below. The optical parameters measured for each of the crosslinked coating layers and shown in Table 1 below were obtained with a Woollam base ellipsometer. Approximately 5 mg of material was weighed and subjected to thermal analysis. For TGA, isothermal holding was performed at 150 ° C., then the sample was heated to 500 ° C. at a heating rate of 10 ° C./min. For DSC, a standard double heating method was performed. The Tg values shown in Table 1 are the average of two tests. The control composition in Table 1 below is a comparative composition containing a polyester resin that does not contain a parabanic acid unit.

表１：パラバン酸含有ポリエステルについての分析データ

Table 1: Analytical data for parabanic acid-containing polyesters

Claims (14)

(A) a layer of the coating composition on a substrate, wherein the coating composition comprises a component comprising one or more paravanic acid moieties; and (b) a photoresist layer on the coating composition layer;
A coated substrate comprising:   The substrate of claim 1 wherein the component comprising one or more parabanic acid moieties is a resin.   The substrate of claim 2 wherein the resin comprises a polyester chain.   4. A substrate according to claim 2 or 3, wherein the resin further comprises one or more cyanurate and / or uracil groups. (A) applying a coating composition comprising a component comprising one or more parabanic acid moieties onto a substrate;
(B) applying a photoresist composition over the coating composition layer; and (c) exposing and developing the photoresist layer to provide a resist relief image;
Forming a photoresist relief image.   The method of claim 5, wherein the component comprising one or more parabanic acid moieties is a resin.   The method of claim 6 wherein the resin comprises a polyester chain.   The method according to any one of claims 5 to 7, wherein the coating composition comprises a component comprising a phenyl or anthracene group.   9. A method according to any one of claims 5 to 8, wherein the photoresist is exposed with 193 nm radiation.   The method of any one of claims 5 to 9, wherein the applied coating composition is crosslinked prior to applying the photoresist composition.   An antireflective composition for use with an overcoated photoresist composition comprising a resin comprising one or more paravanic acid moieties.   The antireflective composition according to claim 13, wherein the resin contains a polyester chain.   The antireflection composition according to claim 11 or 12, wherein the resin contains a phenyl group.   The antireflection composition according to any one of claims 11 to 13, wherein the composition comprises a crosslinking agent component.